Re: [PATCH v8 5/9] seccomp: split mode set routines
From: Oleg Nesterov
Date: Fri Jun 27 2014 - 15:29:43 EST
On 06/27, Kees Cook wrote:
>
> It looks like SMP ARM issues dsb for rmb, which seems a bit expensive.
> http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0204g/CIHJFGFE.htm
>
> ...
>
> I really want to avoid adding anything to the secure_computing()
> execution path. :(
I must have missed something but I do not understand your concerns.
__secure_computing() is not trivial, and we are going to execute the
filters. Do you really think rmb() can add the noticeable difference?
Not to mention that we can only get here if we take the slow syscall
enter path due to TIF_SECCOMP...
Oleg.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/